參數(shù)資料
型號: EVAL-AD5235SDZ
廠商: Analog Devices Inc
文件頁數(shù): 18/32頁
文件大?。?/td> 0K
描述: BOARD EVAL FOR AD5235
標準包裝: 1
主要目的: 數(shù)字電位器
嵌入式:
已用 IC / 零件: AD5235
主要屬性: 2 溝道,1024 位置
次要屬性: SPI 接口
已供物品: 板,CD
Data Sheet
AD5235
Rev. F | Page 25 of 32
BIPOLAR PROGRAMMABLE GAIN AMPLIFIER
For applications requiring bipolar gain, Figure 51 shows one
implementation. Digital Potentiometer U1 sets the adjustment
range; the wiper voltage (VW2) can, therefore, be programmed
between VI and KVI at a given U2 setting. Configure OP2177
(A2) as a noninverting amplifier that yields a transfer function of
K
D2
R1
R2
V
I
O
)
1
(
1024
1
(4)
where K is the ratio of RWB1/RWA1 set by U1.
V+
V–
OP2177
AD5235
VO
V+
V–
OP2177
AD5235
VI
A1
W1
B1
–KVI
A2
B2
W1
VDD
VSS
R1
R2
VDD
VSS
A1
U2
A2
U1
02
81
6-
0
50
C
Figure 51. Bipolar Programmable Gain Amplifier
In the simpler (and much more usual) case where K = 1, VO is
simplified to
I
O
V
D
R1
R2
V
1
1024
2
1
(5)
Table 21 shows the result of adjusting D2, with OP2177 (A2)
configured as a unity gain, a gain of 2, and a gain of 10. The
result is a bipolar amplifier with linearly programmable gain
and 1024-step resolution.
Table 21. Result of Bipolar Gain Amplifier
D2
R1 = ∞, R2 = 0
R1 = R2
R2 = 9 × R1
0
1
2
10
256
0.5
1
5
512
0
768
0.5
1
5
1023
0.992
1.984
9.92
10-BIT BIPOLAR DAC
If the circuit in Figure 51 is changed with the input taken from a
precision reference, U1 is set to midscale, and AD8552 (A2) is
configured as a buffer, a 10-bit bipolar DAC can be realized (as
shown in Figure 52). Compared to the conventional DAC, this
circuit offers comparable resolution but not the precision because
of the wiper resistance effects. Degradation of the nonlinearity
and temperature coefficient is prominent near the low values
of the adjustment range. Alternatively, this circuit offers a unique
nonvolatile memory feature that, in some cases, outweighs any
shortfalls in precision.
Without consideration of the wiper resistance, the output of this
circuit is approximately
REF
O
V
D
V
1
1024
2
(6)
V+
V–
AD8552
VO
V+
V–
AD8552
–2.5VREF
B2
U1 = U2 = AD5235
A2
A1
B1
W2
A1
W1
U1
U2
+2.5VREF
VIN VOUT
TRIM
5
GND
2
6
U3
ADR421
+2.5V
–2.5V
+2.5V
A2
VI
02
81
6-
05
1
U1 = MIDSCALE
Figure 52. 10-Bit Bipolar DAC
PROGRAMMABLE VOLTAGE SOURCE WITH
BOOSTED OUTPUT
For applications that require high current adjustment, such as a
laser diode driver or tunable laser, a boosted voltage source can
be considered (see Figure 53).
AD5235
V+
V–
W
AD8601
VO
A
B
VI
2N7002
RBIAS
SIGNAL CC
LD
IL
02
81
6-
05
2
U2
Figure 53. Programmable Booster Voltage Source
In this circuit, the inverting input of the op amp forces VO to be
equal to the wiper voltage set by the digital potentiometer. The
load current is then delivered by the supply via the N-Ch FET N1
(see Figure 53). N1 power handling must be adequate to dissipate
(VI VO) × IL power. This circuit can source a 100 mA maximum
with a 5 V supply.
For precision applications, a voltage reference, such as ADR421,
ADR03, or ADR370, can be applied at Terminal A of the digital
potentiometer.
相關PDF資料
PDF描述
MCZ33742EGR2 IC SYSTEM BASIS CHIP CAN 28-SOIC
ECM30DCAN CONN EDGECARD 60POS R/A .156 SLD
EVAL-ADCMP561BRQZ BOARD EVALUATION ADCMP561BRQZ
VI-BNB-EW CONVERTER MOD DC/DC 95V 100W
A3AAB-2036M IDC CABLE- ASC20B/AE20M/ASC20B
相關代理商/技術參數(shù)
參數(shù)描述
EVAL-AD5235SDZ 制造商:Analog Devices 功能描述:Evaluation board
EVAL-AD5242EBZ 功能描述:BOARD EVALUATION FOR AD5242 RoHS:是 類別:編程器,開發(fā)系統(tǒng) >> 評估演示板和套件 系列:- 標準包裝:1 系列:- 主要目的:電信,線路接口單元(LIU) 嵌入式:- 已用 IC / 零件:IDT82V2081 主要屬性:T1/J1/E1 LIU 次要屬性:- 已供物品:板,電源,線纜,CD 其它名稱:82EBV2081
EVAL-AD5243SDZ 功能描述:BOARD EVAL FOR AD5243 RoHS:是 類別:編程器,開發(fā)系統(tǒng) >> 評估演示板和套件 系列:* 標準包裝:1 系列:- 主要目的:電信,線路接口單元(LIU) 嵌入式:- 已用 IC / 零件:IDT82V2081 主要屬性:T1/J1/E1 LIU 次要屬性:- 已供物品:板,電源,線纜,CD 其它名稱:82EBV2081
EVAL-AD5245EBZ 功能描述:EVAL BOARD FOR AD5245 RoHS:是 類別:編程器,開發(fā)系統(tǒng) >> 評估演示板和套件 系列:- 標準包裝:1 系列:- 主要目的:電信,線路接口單元(LIU) 嵌入式:- 已用 IC / 零件:IDT82V2081 主要屬性:T1/J1/E1 LIU 次要屬性:- 已供物品:板,電源,線纜,CD 其它名稱:82EBV2081
EVAL-AD5246DBZ 功能描述:BOARD EVAL FOR AD5246DBZ RoHS:否 類別:編程器,開發(fā)系統(tǒng) >> 評估演示板和套件 系列:* 標準包裝:1 系列:- 主要目的:電信,線路接口單元(LIU) 嵌入式:- 已用 IC / 零件:IDT82V2081 主要屬性:T1/J1/E1 LIU 次要屬性:- 已供物品:板,電源,線纜,CD 其它名稱:82EBV2081